The 1.2% figure is for the year not a month, so you don’t need to multiply by 12.
A 1.2% decrease means the earnings in real terms remains almost flat. However, there is serious inflation that is at a much higher rate.
So, relatively from year to year, the wage earner is economically considerably worse off by a factor equal to the inflation rate minus the wage change rate.
6% + (-1.2%) = 7.2% change in buying power